Abstract

The cephalic and thoracic horns of various male lucanid and dynastid beetles have long been considered classical examples of allometric growth, the relation between size of horn and body size being expressed by the exponential equation Y = bXk, where Y horn size, X body size, band k being constants; k is usually referred to as the ""growth coefficient"" of the heterogonic organ. But, as pointed out by Huxley (1931, 1932) there is an important difference between holometabolous insects and other animals exhibiting allometric growth e.g. crabs.